Mazda 3 Sedan 2020 Owner's Manual page 301

Steering assist function
The steering assist function operates when all of the following conditions are met.
Your vehicle is moving and less than about 56 km/h (35 mph).

White (yellow) lane lines on both sides are detected and you are driving near the

center of the lane, or your vehicle detects a vehicle ahead.
The steering wheel is not turned sharply.

The turn signal lever is not operated.

The headway control function is operating.

(Manual transmission vehicle)

The vehicle speed is about 30 km/h (19 mph) or faster.
NOTE
The steering assist function operates so that the vehicle remains near the center of
the driving lane, however, depending on conditions such as the road curvature, road
slope and undulations, and vehicle speed, the function might not be able to keep
the vehicle near the center of the driving lane.
Setting method
1. CANCEL switch
2. RES switch
3. TJA switch
1. Press the TJA switch.
The TJA standby indication (white) turns on. In addition, the TJA display
indication is displayed on the multi-information display at the same time.
When Driving
i-ACTIVSENSE
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